Prop for mines.



Patented Aug-17, 1909.

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UNITED STATES PATENT @FETQE,

FRIEDRICH NELLEN, OF ESSEN-ON-THE-RUHR, GERMANY.

PROP FOR MINES.

To all whom it may concern:

Be it known that I, FRIEDRICH NELLEN, a subject of the German Emperor, and resident of Essen-on-the-Ruhr, Germany, have invented certain new and useful Improvements in Props for Mines, of which the following is a specification.

This invention relatesto improved props for mines which are constructed in such a manner that a tube composed of two semicylinders is filled at the place where the prop is to be used with cores from waste material; said props being particularly designed for use in connection with the supports for mine galleries described and claimed in my copending application for patent, Serial No. 407,418, filed Dec. 20, 1907.

In the accompanying drawings the invention is shown.

Figure 1 represents, partly in section and partly in front view the artificial prop for mines, the front half of the cylinder being removed. Fig. 2 is a section on the line rc-w of Fig. 1, showing both cylinder halves around the prop.

The improved prep for mines consists of a hollow cylinder composed of two semi-cylinders 0 and p of sheet metal, which is held together by detachable clips (7 and filled with a core a made from waste-material particularly rock. The core is composed of several pieces of uniform diameter which have an indentation b at one end and a projection c at the other end so that the projection of the one block fits the indentation of the other Specification of Letters Patent.

Application filed December 20, 1907.

Patented Aug. 1'7, 1909.

Serial No. 107,419.

l block. Between the blocks compressible buffers d are inserted, which are made from cork, wood shavings, straw or similar suitable material. The compressible buffers can also be arranged in the indentations b. The upper core-block f has a semicircular indentation for the reception of the cap 9.

The improved prop for mines made as hereinbefore described is of very great stability and it can even be used without the sheet-metal cylinder when it has once been put up. When a pressure is exerted upon such a prop, the buffers are first compressed before any pressure is exerted upon the blocks.

Having fully described my invention, what I claim and desire to secure by Letters Patent is A prop for mines, comprising in combination a hollow cylinder composed of two semicylinders and means to hold the same together, a number of superposed rock cores having on one side a recess and on the other side a projection to be rigidly built up in said casing, compressible buffers disposed between the single cores, and a cap, the uppermost core having a semicircular groove to receive said cap, for the purpose set forth.

In testimony whereof, I have hereunto set my hand in the presence of two subscribing Witnesses.

FRIEDRICH NELLEN. l/Vitnesses WILHELM FLASOHE, ALEO. P. MANNY. 

